The map you see there is merely an image. I can draw anything I want over the top or on the image itself and then invisibly over the top of that.

So, I basically draw in the DCCB Editor on a transparent layer over the top of the WitE image and you will just see roads on the map when you open the game. The game will treat those as actual roads.

In fact, those are DCCB roads you're seeing in the other Editor Q&A thread, although they need to be re-positioned.

With rail I can use the routes provided by WitE and draw invisible DCCB rail lines over the top so that the game sees a rail line in the same place as the WitE line. If I create two rail classes (same properties but one opaque and one transparent) then I can also add missing rail lines to the edited map. They will look slightly different, but that's a trade off.

I'm just experimenting and I'm not convinced yet that this is the right direction to take. Some other imported images might work better, but people had expressed an interest in a WitE mod here.

will 2by3 support this? or is this already a modded wite map? looks cool!

Well, I'm not selling it and it's a bitmap in a game I own, not code, so I believe I can use it for modding purposes. They should take it as a compliment and recognize that it also promotes their title, sold via the same publisher.

The full size images have also been in the public domain for over a year, in the forum moderated by a rep from the developers and also accessible via at least one online Wiki.